package demo3;

import demo2inter.ITestInterFace;

public class Computer {
    public void powerOff (){
        System.out.println("关闭电脑！");
    }
    public void powerOn(){
        System.out.println("打开电脑！");
    }
    public void useDevice(IUSB usb){
        usb.openDevice();
        //这里要区分 USB引用了哪个对象
        if(usb instanceof Mouse){
            Mouse mouse =(Mouse) usb;//向下转型
            mouse.click();
        }

        //调用键盘
        if(usb instanceof KeyBoard){
            KeyBoard keyBoard=(KeyBoard) usb;
            keyBoard.input();
        }

        usb.closeDevice();
    }

    public static void main(String[] args) {
        Computer computer=new Computer();
        computer.powerOn();


        computer.useDevice(new KeyBoard());
        computer.useDevice(new Mouse());
        computer.powerOff();
        IUSB.testUSB();//调用接口IUSB中 利用static 修饰的

    }
}
